The present invention relates to blind fasteners for securing workpieces together and more particularly to a multiple piece blind fastener including a pin (or spindle) and a sleeve and including means for compensating the fastener for use over a wide range of total thicknesses of workpieces to be secured.
Examples of multiple piece blind fasteners can be seen in the following U.S. patents: No. 3,148,578 for "Rivet and Method of Riveting", issued on Sept. 15, 1964 to Gapp; No. 3,302,510 for "Die-Draw Blind Rivet with Non-Deforming Die", issued on Feb. 7, 1967 to Gapp; No. 3,369,289 for "Die-Draw Blind Rivet with Deformable Die and the Method of Setting Same", issued on Feb. 20, 1968 to Gapp; No. 3,390,601 for "Blind Fastening Devices", issued on July 2, 1968 to Summerlin; No. 4,012,984 for "Blind Rivet Assembly With Locking Collar on Rivet Stem", issued on Mar. 22, 1977 to Matuschek; No. 4,312,613 for "Blind Rivet Assembly", issued on Jan. 26, 1982 to Binns; and No. 4,364,697 for "Blind Fastener Assembly", issued on Dec. 21, 1982 to Binns.
In many blind fastener applications it is desirable that one fastener have a wide grip range, i.e., be capable of securing together different groups of workpieces varying in total thickness. At the same time it is also desirable that the fastener have the capability of pulling the workpieces together, i.e., pull together. It is also desirable that the fastener form a blind head having a relatively large surface, i.e., "footprint", in clamping engagement with the blind side of the workpieces. In many applications it is also desirable that, after installation, the pin and sleeve are mechanically locked together.
In the present invention a novel multiple piece blind rivet is provided which includes a grip adjustment means. The grip adjustment means functions to assist in the expansion of the blind side of the sleeve and to provide an enlarged footprint to enhance clamp retention between the workpieces. At the same time the grip adjustment means is constructed to deform radially outwardly to varying extents whereby its length will be varied accordingly and whereby a wide grip range can be accommodated by a single fastener construction. The grip adjustment means in assisting the formation of the blind head on the sleeve also promotes pull together of the workpieces.
Therefore, it is an object of the present invention to provide a novel multiple piece blind fastener having grip adjustment means for providing a fastener with a wide grip range.
It is another object of the present invention to provide a multiple piece blind fastener having means for providing good pull together of the workpieces being secured. It is still another object where such pull together is enhanced by the grip adjustment means.
It is another object of the present invention to provide a multiple piece blind fastener having means for providing a blind head having an enlarged "footprint" on the blind side of the workpieces. It is another object where the formation of such enlarged "footprint" is enhanced by the grip adjustment means.
The fastener of the present invention also provides means for locking the pin or spindle and collar together with an internally formed lock. Examples of internally formed locks for blind fasteners are shown in U.S. Pat. No. 3,288,016 for "Blind Two-Piece Fastener", issued on Nov. 29, 1966 to Reynolds; see also the copending application of Walter J. Smith for "Two Piece Blind Fastener with Lock Spindle Construction", Ser. No. 425,304, filed Sept. 28, 1982, commonly assigned to Huck Manufacturing Company, and U.S. Pat. No. 3,915,052 for "Self Broaching Fastener Assembly And Like Self Sizing Fasteners", issued on Oct. 28, 1975 to Ruhl. The lock construction in the present invention functions substantially by extrusion and hence forms the internal lock by engagement of a lock shoulder in the sleeve by an extruding land on the pin; in this manner the material for the lock is formed substantially by extrusion or metal flow radially inwardly with minimal, if any, shearing of the collar lock shoulder. This construction also facilitates flowing of the sleeve shoulder material radially outwardly to provide hole fill over a significant length of the collar shank.
Therefore, it is another object of the present invention to provide a novel multiple piece blind fastener construction including a novel construction for locking the pin and sleeve together. It is still another object of the present invention to provide a novel construction which locks the pin and sleeve together while providing hole fill.
It is a general object of the present invention to provide a novel multiple piece blind fastener.
Other objects and advantages of the instant invention will be apparent in the following specification, claims and drawings.